Muse Auth

Use Meta Muse Spark in opencode billed to your Muse Code monthly subscription — no pay-as-you-go API key, no third-party CLI.

Unofficial and experimental. This plugin uses a Muse Code subscription credential from opencode. Meta's terms limit that credential to Muse Code, so this use may not be supported and Meta may suspend or revoke accounts or credentials. Use it at your own risk; the authors cannot recover an account. Read DISCLAIMER.md before installing.

Install

// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "plugins": ["opencode-muse-auth"]
}

Then run /connect in opencode, pick the meta provider and the Muse Code subscription method: it shows a Meta device page URL and a code. Enter the code in your browser (your own Meta account) and the login completes by itself.

Verified end-to-end against the published package: isolated project with only "plugins": ["opencode-muse-auth"], live chat on meta/muse-spark-1.3 billed to subscription.

Requirements

• opencode with plugin support
• A Meta account with an active Muse Code subscription

How it works

The plugin registers an auth hook for the built-in meta provider (Routes through the Responses API, meta.txt system prompt applies automatically to muse-* model ids):

• Login — Meta device-code exchange (RFC 8628) inside /connect, then mints the stable account-bound inference key via the Model API. The key is never printed and the OAuth access token from the login flow is kept in memory only.
• V1 storage — OpenCode's auth store is the primary source; the auth loader falls back to the legacy cache (~/.config/opencode/muse-code-sub.json) only when the store has no key. The cache is still written so upgrades keep working.
• V2 storage — the credential lives in OpenCode's integration store; the plugin does not write the local cache on this path.
• Runtime — the mint endpoint is aggressively rate-limited, so the plugin never re-mints on its own; re-run /connect only if access is revoked (401).

Flow parameters are compatible with the published behavior of oh-my-pi (MIT); see NOTICE and AUTH_CONTRACT.md.

Credentials and removal

The inference key is held by OpenCode (V1 auth store or V2 integration store); the legacy cache, when present, stores only apiKey, accountId, and email. The OAuth access token is never written to disk. To remove access:

• disconnect the provider or log out in OpenCode (this removes the key OpenCode uses; the store is ~/.local/share/opencode/auth.json);
• delete ~/.config/opencode/muse-code-sub.json if it exists from an older version;
• run muse logout if you also want to clear the Muse Code CLI session;
• remove opencode-muse-auth from opencode.json.

Development

npm install
npm run build
npm test

License

MIT — see LICENSE. The software is provided "as is"; see DISCLAIMER.md for the risk notice and liability terms.